[SCSI] sd: Use SCSI read/write(16) with > 32-bit LBA drives
Force large capacity (> 0xFFFFFFFF blocks) drives to use READ/WRITE(16) instead
of READ/WRITE(10). Some(most/all?) USB enclosures do not like READ(10) commands
when a large capacity drive is installed. This issue was reported and discussed
here: http://marc.info/?l=linux-usb&m=135247705222324
Signed-off-by: Jason J. Herne <hernejj@gmail.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index a45e12a..c5a189c 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1011,7 +1011,7 @@
SCpnt->cmnd[29] = (unsigned char) (this_count >> 16) & 0xff;
SCpnt->cmnd[30] = (unsigned char) (this_count >> 8) & 0xff;
SCpnt->cmnd[31] = (unsigned char) this_count & 0xff;
- } else if (block > 0xffffffff) {
+ } else if (sdp->use_16_for_rw) {
SCpnt->cmnd[0] += READ_16 - READ_6;
SCpnt->cmnd[1] = protect | ((rq->cmd_flags & REQ_FUA) ? 0x8 : 0);
SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
@@ -2203,6 +2203,8 @@
}
}
+ sdp->use_16_for_rw = (sdkp->capacity > 0xffffffff);
+
/* Rescale capacity to 512-byte units */
if (sector_size == 4096)
sdkp->capacity <<= 3;